Improved does not adequately describe all the upgrades found in the Kowa BD XD 42mm binocular. Prominar XD objective lenses significantly decrease chromatic aberration and deliver high-contrast images. Enhancements to the BD XD binocular design include additional eye relief, an expanded field of view, a 4.9 feet close focus, a smaller and lighter size, and rugged magnesium housing. Add it all up and no matter how you use it, the Kowa BD XD is built to excel.